Do your new metal ones have an adjustable pivot at the clamp?
My plastic version was locked in one position and I had to almost completely remove the bolt before the arm would rotate out of the way.
I would have glued a piece of an Allen key into the bolt head so I could loosen it easily, but not if it needed half a dozen full rotations to loosen it enough.
No. Those claps are re-used from my old Hafny mirrors and pretty much same as yours. So yes, adjustments are quite tedious to do, but I don't need to do them often. The clamps from my mirrors were very bulky to be used on my quite small and busy handlebars, so keeping the old clamps was reasonable compromise which worked.